(1) Field Of The Invention
The invention relates to an inclined bucket elevator which can receive loose materials or articles at a low elevation, raise and transfer them, and then discharge them at a higher elevation. The bucket elevator, according to the invention, comprises a plurality of independent, slidable, unconnected, free buckets which can be slid along an endless inclined track. The buckets can be removed from the elevator by use of a detachable track section.
(2) Description of The Prior Art
Bucket elevators, according to the prior art, typically comprise one or more endless bucket carriers, such as chains, driven by suitable drive means, such as upper and lower sprockets, and having open-topped buckets attached thereto at selected positions thereon. During their ascending movement, the buckets carry loose material or articles from a lower to a higher elevation at which the material is discharged. The buckets are returned to the lower elevation in an inverted condition and thereafter they become upright again for refilling and then repeating the cycle of operation.
Chain-type and belt-type bucket elevators are generally cumbersome, noisy in operation, and require frequent maintenance and lubrication. Moreover, connecting the buckets or other load-carrying members to a chain or chains not only contributes to the cost of manufacturing the conveyor, but also the links of the chain or other parts of the connecting structure elements are prone to frequent breakage which interrupts the operation of the conveyor.
The prior art bucket elevators are also unsatisfactory for use in situations in which a high degree of cleanliness and the maintenance of sterile conditions are required, such as in the pharmaceutical industry. For example, in the pharmaceutical industry, in some situations it is desired to use an inclined bucket elevator to elevate and transport pills, tablets or capsules from a low discharge point of one machine to a hopper for an adjacent machine or to a large drum. Since the buckets are typically connected to a driving chain or chains by pivot or link mechanisms, it is difficult to completely clean and sanitize these prior art bucket elevators. It is difficult to remove the buckets from the driving chain or chains and, therefore, the buckets cannot easily be sanitized.
Another problem with the prior art elevators used in the pharmaceutical industry is that unit dosage forms, such as tablets, typically leave a machine, for example, a tablet compressing machine, at an elevation which is so low that they cannot be fed into the prior art bucket elevators. As a result, in the past, the tablets have been discharged into small receiving boxes and, from time to time, the tablet press operators then manually dumped the contents of those small boxes into a larger container. The small receiving boxes are likely to fill up within a short period of time and a large amount of operator time is required to monitor and dump those small boxes. Therefore, there is a need for a bucket elevator which can receive objects, for example, tablets, at a low elevation, elevate and transport them, and then discharge those objects at a higher elevation, and which requires minimum maintenance and is readily capable of complete cleaning and sanitization of the buckets with a minimum amount of difficulty.